For example: solvent-UV (SUV) – the latest technology to hit the wide-format inkjet market – the development of which owes a lot to looking to past innovation. 

SUV is a hybrid technology that, as the name suggests, combines aspects of solvent and UV-cured inks in an attempt to produce ink that offers the best of both worlds.

There are three firms offering SUV technology: Colorific with its Lightbar system, Fujfilm with its Fuze technology and Vybrant F1600 printer, and Mimaki with its SUV printers and ink. 

Mimaki first showed a prototype in 2012, along with its own latex technology, launching the product the following year. Colorific says it has been working on the technology since 2012 when it was approached by an unnamed ink manufacturer with the technology and asked to take it to market, which it did in 2013. Fujifilm was, publicly at least, last to the party, showing its technolgy at Fespa 2014, followed by sales in Germany. Roll-out to the rest of Europe will begin after Fespa 2015.

Despite strong evidence that the core technology is the same (Fuji’s Vybrant F1600, for example, is based on a Mimaki), no firm will confirm it, citing non-disclosure agreements. However, even if there are differences in the details, it is a new class of ink. In that way its development is similar to HP and Mimaki coming up with latex inks, which although different implementations are both water-based thermo-setting resin inks.

Solvent ink still dominates the market, making up three fifths of the volume used, according to figures from industry research firm Infotrends. UV-curing accounts for a fifth, with water-based (AKA aqueous), including latex, making up the remaining fifth. 

Solvent and water-based inks have been around since the earliest days of wide-format inkjet, while UV-curing was pioneered in around 2000 by what was then Sericol, and is now Fujifilm Speciality Ink Systems (FFSIS). 

Cost benefits

FFSIS was keen to expand the uses of UV-curing in wide-format but encountered technical and financial barriers. Most UV printers have curing lamps on the same carriage as the printheads, adding bulk, complexity and cost. While high-volume users can recoup the cost, for the majority of printers using roll-fed solvent printers costing below £20,000, it’s untenable due to lower production volumes. 

“A conventional UV machine of a similar specification would be in the region of £30,000-£50,000, so no longer within reach of the core customer,” says Fujifilm European group marketing manager Tudor Morgan. “We needed a way to provide the benefits of UV at a price point and performance more people were used to.” 

While Fuji was the last to go public on SUV, it was beavering away five years ago, inspired by the approach taken 30 years before.

“I can remember back in the 80s when screen printers using solvent inks were looking to switch to UV inks,” says Morgan. “The solution back then was a clip-on UV curing unit that could fit between the screen and the drier.”

He wondered if the same concept could bring the advantages of UV-cured inks to a broader section of the wide-format inkjet market. The idea was that a standard roll-fed solvent printer – as produced by the likes of Epson, Mimaki, Mutoh, Roland and Seiko – could be fitted with a fixed UV curing lamp beneath the print carriage. 

The price of adding the curing system comes out at around £2,500, far more affordable than the additional £10,000-£30,000 required for a UV printer.

For Fuji, SUV is a way for it to take its success in UV at the top end of the market to a broader sector. But there are advantages of SUV for printers too. 

The price of a system is attractive, as is the ink, which is the same per litre as eco-solvent. That isn’t the whole story though with Colorific saying that customers get more metres per litre for equivalent quality output. Additionally SUV possesses a lot of the positives of both solvent and UV-cured inks without some of their negatives. 

From the UV side of things the instant curing and robustness are key attributes. In particular the ability to instantly finish and ship prints rather than waiting 24-48 hours for solvent inks to fully de-gas.

“If you need to leave a job for 24 hours before you can do anything with it you can’t solve that with a quicker printer,” says Colorific Solutions business development director Shaun Holdom.

An example is Smart Print, a four-staff firm in Garston, Liverpool, which offers design, print and fitting of a range of print including posters, shop signs and banners and became one of the early users of Colorific’s Lightbar. 

“Now we can guarantee a same-day service; if someone comes in with a job that they need in a hurry we can get it done by 4pm,” says managing director Peter Kennedy. 

Kennedy highlights another problem with solvent’s need for de-gassing – space. “We’re on the high street, it’s a small site and there’s no room for storage.”

Another UV attribute is robustness; SUV is tough enough to eliminate the need for lamination in a lot of cases, saving time and money.

“For the stickers and signage we do it’s been useful as we don’t need to laminate any more,” says Neil Herbert director of Ryde, Isle of Wight-based DNN Signs. “The ink is more durable; on our old machine almost any solvent would cause the image to lift off.”

Mimaki distributor Hybrid Services sales manager John de la Roche adds: “Wall coverings are another good application for SUV. In environments like hotels, that are likely to get abused, its robustness is popular.”

For Kennedy familiarity and continuity were crucial, for both hardware and substrates. It fitted its Lightbar to an existing printer.

“We’ve always had Roland printers and we wanted to stick with them,” he says, adding: “It works perfectly with our existing materials. The majority of our work is banners and it just sits there churning them out for six or seven hours a day.”

Substrate flexibility

De la Roche also highlights substrate range: “It’s not limited by materials. The range is wider than with latex, which has a problem with heat-sensitive materials.”

SUV can produce the same high-resolution, small sharp dots as solvent with deep blacks and a wide gamut and has the same thin ink film, as opposed to the prominent relief of UV. That ensures the printed image matches the finish of the substrate. On high-gloss materials the results are glossy, rather than the satin or matt finish typical of UV.

There are a couple of applications that it is not so well suited to. Backlit and translucent jobs that rely on white are still better served by UV, as there is no white ink for any SUV machine. There is debate about how suitable SUV is for vehicle graphics and whether that’s a fundamental problem or just current implementations and fitter experience. 

“It’s not got as much elasticity as true solvent, so it’s not the first choice for wrapping,” says de la Roche. “However, because of the robustness it is used for vehicles but tends to be for flat panels.”

Colorific’s Holdom is more positive, and says the firm is looking at getting warranty backing from the self-adhesive vinyl producers.

It’s still early days for SUV, but it’s getting closer to critical mass. Colorific is just shy of 100 Lightbar installs in the UK and is poised to expand into Europe now the concept is proven. Fuji, as mentioned, is about to roll out across Europe. Hybrid is coy about unit sales but does report healthy inks sales. So, lessons from the past have been proven in the present and SUV has a positive future. 

Case study: Harrisons Signs

York-based Harrisons Signs made its first move into wide-format digital printing at the turn of the 21st Century. The wide range of applications that inkjet can produce led to expansion beyond signage into posters, banners and POS. 

The firm is a longstanding Mimaki user having had a succession of machines, most recently a 1.3m-wide JV33. A couple of years ago the need to increase throughput led it to look at new equipment. “We had a bottleneck in printing, which was causing us problems with our lead times, so we were looking for a second printer,” says account manager Peter Robinson.

Initially the company was considering an HP Latex model, however, when Robinson went for the demo, he saw a Mimaki SUV, which he had been previously unaware of. 

“We were attracted to the instant drying and the fact that we wouldn’t have to laminate,” says Robinson. “On the JV33 everything was laminated as if we didn’t there was a risk that the ink would smudge. For the fear of de-lamination with solvent we’d never rush a job - you can’t risk it.”

That meant a couple of days were needed after printing to de-gas before laminating. 

“With the SUV all jobs are dry and ready to go and the only thing that we laminate are long-term outdoor graphics. It’s great for rush jobs. Not everything needs to be turned around same day but now when it does we can do it.”

Since installation in January 2014 the SUV has become the firm’s workhorse machine.